Charge forming device



Oct. 20; 1953 E. H. FCSTER CHARGE FORMING DEVICE 1 MT H a u m v a e L w 4 1 2 F a J w 7 H 2 m l A L $7 1 1 W 0 7. 6 n i D 7 E 0 u 0 1 0 1 3 5 u mJn! B F- E .D Y in a awmfl. 6 I V 1 4. 6 J m 1, a m

m 4+ J .w m

Oct. 20, 1953 E. H. FOSTER 2,656,166

CHARGE FORMING DEVICE Filed July 12, 1949 2 Sheets-Sheet 2 155 15.4 (4 52 I 4 mi- :10 6% s 63 .56: 7 gfl i h I 43 59 105 71 I i H i H.411 a .A I 5 w Hi? I 41 a1 a, .44 mm Patented Oct. 20, 1,953

UNITED STATES PATENT OFFICE Tillotson Manufacturing Company,

Toledo,-

-Ohio, at corporation of Ohio Application :Iuly12, 1949, SerialNo. 104,225

:13 Claims.

This invention relates to "charg "forming apparatus for use with internal combustion engines and more especially to a cai'buretorofachzracter particularly adaptable for "use with-comparatively small internal combustionengines havin-g relatively small piston' 'displacement of acharacter particularly adaptable for drivingor operating bicycles, motor cycles, 'lawn mowers, small garden tractors, -mari'ne engines, stat ienary industrial engines and *thelike.

The invention embraces the provision of a carburetor device wherein the "elements thereof are assembled and'c-ompa'cted to occupy a rela- :tively small space so as torender-the 'device readily adaptable for use with engines 1 wherein only a limited space is availa'ble for a carburetorde- 'vice.

The invention furthercomprehends theprovi- :sion of a carburetor in Wh-ich the-iloat chamber adapted to containiuel supply' 'is disposed direct- Zly beneath a mixing passage-so as to'minimi-ze' the distance throughwhich-fuel must be elevated for discharge into the mixing passage of the carburretor.

T An object ofthe =inverltion is the provision of or passage for conveying f-uel to anidle jet and ,also serving as anadjustment for-metering fuel :to a fuel supply well-in the carburetor.

Still another object ofthe invention-"resides inthe arrangement and construction-of a float 'chamber, fuel well andmixing 'passagewherein :a minimum amount of lifting force is required to discharge fuel from a main orifice-'orinoz'zle'into a mixing passage.

Still another object of'thefinvention'is the provision of a combined "idle fuelsupplytubeand imetering device extending throu'gh a' high speed ;fuel discharge orifice, the idle tube and metering device being out 'of alignmentfiwith the axis of the main fuel dischargeori'fice'wherebythe major amount of fuel"discharged fromthe high speed vjet is emitted"into-a m'iiiing passage at-one'side of the idle tube andmet'ering device.

Further objects and advantages are within the" scope of thisinventioni'such as-"relate' tothe-ar rangem'ent, 'operation'and function of theirelatted elements of the structure, to various details of construction and toicombinaftionsmf" parts, ele 'mentsper "se; "9Jnd""'50" economies""oFmanufacture' and numerous other features as will be apparent from a consideration of the specification and drawing'of a form of the invention,which may be preferred, in which:

Figure-1 is 'a top plan view illustrating one form ofcarburetor of my invention;

Figure 2 is a verticalsectional View through the carburetor, the sectionbeing taken substantially 0n the-line 2-2 of Figure 1;

Figure 3 is a vertical sectionalview taken substantially on the'line 33 of Figure 2;

Figure 4 is a fragmentary detail sectional view taken substantially on the'line 4-4 of Figure 3;

Figure '5 is a transverse sectional View taken substantially on the 1ine i5.5 of Figure 3;

Figure 6 is a fragmentary sectional view taken substantially on the line'66 of Figure 1.

While I have illustrated my invention as embodied in a carburetor especially-adapted for use with comparatively small internal combustion engines, itis to :be understood that I contemplate the utilization :of the principles of my invention in any device whereinrthelsamemay be foundto be applicable.

Referring to thesdrawings indetail, the carburetor is. inclusive of a body I!) beneath which is arranged a fuel receptacleor float. bowl H, a gasket l 2 :being-interposed-between the float bowl and the body forsestablishing .a fluid tight joint between theseeelements. "Thebowl H is .of hollow'comiguration forminga chamber 14 adapted to contain fuel to be, discharged through suitable jets ashereinafter explained. The bowl member H is provided with-a flange portion [3 having a :plurality :of openings l5 adapted to receive screws It for securely fastening the :bowl member I lto the carburetorbody Ill.

The :bowl member I l is formed with a 'bossportion' i8:which is drilled -and:.threaded to accommodate a fittingrzil to which is connected, a' tube orconduit 2! for conveyi g. fuel orgasoline from a tank or reservoir ('not'shownl to the carburetor. The boss I8 is formed with a bore 23 which-is in communication through the fitting 20- with the fuel conveying tube 2!. a'second bore 24 being arranged substantiallyat rightangles to the bore 23 and intersecting'the:same. The passage ml is drilled-into'therboss :lllaand theentranee portion threaded to receiveaqplug:26c1osing the outer end of: the passagei as; shown in Figure 5. The boss 18 is provided with a pair ofaxially arranged bores or chambers 28 and 29 as shown in Figure 5, a portion oftheinner walllof the smaller bore 28 being. threaded to accommodate a valve cage .or .fitting 36. .The fitting 39 is provided with a longitudinal. channelorbore 3t whichaccommodates .a valve member 32 having a polygonally-shaped body and, a. tapered. extremity 33, the latter extending into, an orifice 3 formed in the fitting 30, :the position of the valve 32cctermining the'rate'of flowof'fuel'through the orifice 34 and along the facets of the polygonallyshaped body of the valve into the chamber 29. A portion of the wall 29 is threaded to receive a plug 36 so as to close the chamber 29.

Float means are provided for controlling the position of the valve 32. Disposed within the chamber M is an annular or doughnut-shaped iloat 33 preferably made in two cup like portions 48' and ii which overlap as shown in Figure 6, a

the juncture or overlap seam being soldered or otherwise hermetically sealed. The walls of the cup like portions it and ti comprising the float member are comparatively thin and are fabricated of a metal which is noncorrosive and will not be affected by the liquid fuel. soldered or otherwise secured to the float 35 is an arm d3 having laterally spaced cylindrical portions ts as shown in Figure 4 through which extends a pivot pin or pintle #35 providing a fulcrum for the float 39. pending portion 453 provided with a slot 21 which accommodates a tenon or reduced portion 38 formed on the needle valve 32 as shown in Figure 6. A head portion d9 is formed on the needle valve 32 adjacent the reduced portion the head forming an abutment arranged to be engaged by the depending portion 5 6 when the fuel level falls or is lowered in the chamber is which in turn causes the float to swing downwardly about the fulcrum pin 55 moving the needle valve 32 to open position. Through this connection between the fioat S5 and the needle valve 32, the position of the float controls the flow of fuel into the chamber i i.

The carburetor body ii} is formed with an air inlet passage 52 which may be connected with a suitable air inlet tube 53 if desired. The latter may be connected to an air cleaner or filter (not shown) to admit clean air into the carburetor body. The air passage or inlet 52 is of cylindrical configuration, and disposed in the passage is an air regulating or choke valve 55 which is of disk-like formation and is secured to a transversely extending shaft 5%; by means of a screw 5'! or other suitable means. The air controlling valve 55 may be formed with small openings 58 to admit the passage of some air through the carburetor even when the valve is in closed position as indicated in dotted lines in Figure 2. The air valve operating shaft 5 5 is journaled for rotation in suitable boss portions 59 and 88 formed on the carburetor body. Fixedly secured to one end of the shaft is an arm 62 which is connected to an operating rod 63 for manipulating the air or choke valve 55. A coil spring 64 surrounds the other end of the shaft 55, one end of the spring extending into a slot t5 formed in the shaft, the other end of the spring being secured to the carburetor body by means of a screw 65. The spring St is coiled or stressed to exert a rotative tension upon the shaft 56 tending at all times to urge the air valve 55 to open position as shown in full lines in Figure 2. An abutment pin or stop 58 is fixedly secured in an opening in the wall of the air passage, the pin being engaged by the valve disk 55 to determine the full open position of the valve.

A mixing passage 75 is formed in the carburetor body and is inclusive of a venturi ii having a restricted throat portion E2, the inlet end of the venturi being in direct communication with the air inlet passage 52, the other end of the Venturi configuration being in communication with a cylindrical outlet passage is provided in the body and forming part of the mixing pas- The arm at is formed with a desage. As particularly shown in Figures 2 and 3, the axis BB of the venturi and mixture outlet passage 13 is below the axis AA of the air inlet passage 52 of the carburetor. By positioning 7 the axis of the venturi in the manner shown in the drawings, the fuel discharged into the venturi from a discharge orifice or jet hereinafter described does not have to be elevated or lifted but a comparatively small distance above the fuel level in the chamber id. Disposed in the mixture outlet passage is a circular disk-like valve 16 which functions as a throttle valve for controlling the flow of fuel and air mixture to an engine manifold 77. The valve "it is moun ed upon a transversely extending shaft "is which is journaled in bosses 8s and 8! formed in the body of the carburetor, the valve disk "it being secured to a central flattened portion of the shaft it by means of a screw 82 or other suitable securing means. The valve disk is provided with two or more small openings 83 to provide for passage of a comparatively small amount of air through the carburetor to be mixed with fuel for engine idling purposes in a manner hereinafter explained. An abutment or stop means in the form of a pin 85 is provided as shown in Figure 2 to determine the full open position of the throttle it, full open position being illustrated in dotted lines in Figure 2. The pin is securely driven into a suitable opening in the wall of the passage 13. The shaft '59 is urged toward closed position under the influence of a coil spring is which is similar in construction to the spring 6d. The opposite end of the shaft is equipped with an arm 8:3 to which a throttle operating link 86 is connected for manipulating or regulating the throttle opening position of the valve disk '56.

The carburetor arrangement of my invention is provided with a fuel well and main ncz construction contained within the central space formed by the doughnut shaped fioat carburetor body it is integrally formed with a depending projection or boss 3? which is provided with a central bore 3 5, a portion of the bore being threaded as at as to receive the threaded portion of a fitting 5d. The fitting 33 is formed with a sleeve-like extension S2 within the upper portion of which is snugly fitted a tube 92, the upper end its thereof being open and forming the main fuel jet or orifice through which fuel for high speed operation of the engine is discharged into the venturi to be mixed with air entering the air inlet The sleeve like extension in of the fitting is provided with a cylindrical recess or chamber 3d which is in communication with the air inlet chamber by means of a passage The sleeve-like wall 9! is provided with two or more minute openings or orifices 9:"; for establishing comniunication between the space or chamber at and the interior well 9? formed in the i g 955. The well 9'! in the fitting 9d terminate its lower end in a restricted orifice $55, the latter providing for the admission of fuel from the fioat chamber it into the Well 53?.

The carburetor body i6 is formed with an upwardly projecting portion Hi8 provided with a threaded bore adapted to receive a threaded fitting i02. The axis DD of the fitting I92 is out of alignment with the axis EE of the fitting 90 for a purpose to be hereinafter explained. The fitting N32 is bored in its lower portion to snugly receive a tubular member I03, the latter terminating in a tapered solid end portion I0 3, the latassessor ter "forming a needle-like configuration adapted to extend into the orifice 98 for regulating the fuel flowtherethrough. The fitting 1:02 is provided with a bore 106 which in turn .is in communication with a chamber II]?! by means of a passage I118, thechamber I03 being formed as an annular recess in the fitting 1 02. Thepassage :or chamber :III I is in vcommunication with a channel I'I-Il which terminates in a chamber H2, a

portion of the chamber wall being threaded to accommodate an adjustable valve fitting H3. The carburetor body I0 is formed with a boss portion IIB-having a passage II I drilled therein which establishes communication with chamber I I2 for admitting air into :the chamber from the air inlet passage .52 or from outside atmosphere. The purpose of passages III-ll, II"! and chambers I01, H2 is to admit air for admixing with liquid fuel to provide a combustible mixture for engine idling purposes. The valve fitting H3 is provided with a finger piece or knurled portion HR to facilitate manipulation of the position of the needle valve H9 forming a part of the fitting H3 for controlling the amount of air admitted to the passage ,IlIl. A coil spring I20 surrounds a portion of the fitting I I3 and serves the purpose oflsettingup ,a frictional component between the fitting and the threads in the bore accommodating the fittingsc that the needle valve I I9 will be frictionally retained in adjusted position.

The fuel supply for the idling mixture is obtained frompthe fuel well 91, The member I03 is of hollow configuration throughout a portion f its fing h providing a fuel conveyin Passage I23. The lower extrem 0 h m F is r vided with an orifice I24 for bh hm now of fuel from Well 9' into the passage 423 in member N33. The bore I03 and orifice I08 provide means for establishin communication for flow of liquid fuel from passage I23 into the h mber It? formed n the t in A p sage I26 establishes communication between chamber I01 and a chamber I21, as shown in Figure 2. The chamber I2! is in commumcation with the mixture outlet 13 by means of onfices I25 and .29 which are arranged respectively on each side of the throttle valve disk 16 when the latter is in closed position, as shown in Figure 2. The passages or orifices I28 and 129 are drilled into the carburetor body after which the chamber I2! is closed through the use of a Welsh, plug 13 The passage I26 is drilled or zon a l e carburetor body a d, e e f the pa sa e close y means of a fnct o p u it The. fit in M12. is pro ded th a. t ansv rs ly ext din pin 33 form n a. h nd for ro atin strun m2 a d tube ms in order t0, adlu$ th position o the ne dle 4, A coil spr1ngI34 is disposed tw en tw disks o w she s I35 to set up a f icti n or e asa st he fittmg m order to unusual y et n t e fitting H12 in ad- I 'usted osition.

J It 'slfo uld be no ed tha th s DD of the threaded bore in the carburetor body accommoin the fitt n W2 is sp s d lig y arwads f means- B o the' orem the cranes.-

i mm dating, the fi ing an. Through ngernent of oifset bores, the tube orfuel reg ating means i3. is caused tov occupy a slight- 1y vangular osi on n Figure 2 so that thes irface of the tube substantially in con tact with the u per ed e of;the lush peedv fuel, jet 9% as indies d at tab T is. con truct on places, the o tlet in th let or orifice.

6 93 to theri nt handside of the tube was asshown in "Figure "2 so that the major amount of fuel flowing from the jet 93 is emitted to the right hand side ofthe tube H13.

The function and operation of the carburetor of my invention is as follows: Assuming that the carburetor is connected to an engine manifold :TI and the bowl --II connected to a fuel supply reservoir (not shown) by means of the tube 2|, the float member 39, through its lever moment about the fulcrum 45 is at its lowermost position in which it acts upon the valve member 32 to move same from its seat and thus admit liquid fuel into the float chamber I4 through passages '23, 24 orifice 34 past the polygonally-shaped valve member 32 into the chamber I4. As the fuel level rises in the chamber I4, the float 39 is buoyed upward, moving in a counter-clockwise direction about the fulcrum 45 as viewed in Figure 3, and when the fuel reaches a predetermined level as indicated at L shown in Figure '6, the valve 32, through pressure of the arm 43, closes the orifice 34- to interrupt the flow of fuel into the chamber I4. The member I03 is adjusted through manipulation of the handle portion I33 so that the tapered needle Hid is moved away from its seat to admit fuel from the chamber I4 into the well "or chamber 37 and into the space or well 94 surrounding the fitting 9d. The fuel level in the wellsor chambers 94 and 91 will be thesame as the fuel level in the float chamber I4 in accordance with well known hydrostatic principles. A normal fuel level in the chamber vI4 is indicated at L'.

- Upon the application of a starting force or medium applied to the internal combustion engine with which the carburetor may be used, a subatrnospheric pressure is set up within the passages 52, 73 and the venturi 10. With thernixture controlling valve I6 moved to open or partially open position and the air va1ve58 in closed or partially closed position, the subatmospheric pressure in the mixing passage is effective in the float bowl I4 and well .91 causing fuel to be elevated in the space between the sleeve 92 and the exterior wall of the member I03 and discharged into the venturi or mixing passage from the main orifice or jet 93. When this fuel flow has begun and the engine started, the air valve to admit an increased amount of air to be mixed with the fuel discharged into the venturi Iiland the mixture outlet passage 73. The fuel in the wells 94 and 9? is premixed with a small amount of air supplied through the-air bleed passage 95 so that the fuel discharged from the jet'93 is partially atomized. Due to the positioning of the main jet 913 at the throat or restriction 12 of the venturi I'd, which is at the point of the highest air velocity, it has been found to enhance the operation of the carburetor by providing themajor fuel outlet space at the right side of the member Iil3- at the jet 38. This structural feature decreases the tendency for air pressure to build up on the left hand side of the member I03 as viewed in Figure 2 which may under certain con ditions act in a downward direction upon upwardly moving fuel and impair the-efficiency of fuel discharge from the-main jet 93.

The orifice or passage I23 supplies a mixture of fuel and air for idling purposes of the engine when the valve 15- is in closed position as illustrated in figure 2; The fuel for the idling mixture is obtained from fuel in the well 9:! flowing through orifice I24 upwardly through the hollow interior I23 of member I63 thence through the orifice I03 into the chamber 101 formed in'the fitting I02. The fuel introduced into the chamber I! is therein mixed with air from the sup- 'plemental air passage III) so that a fuel and air mixture is conveyed through passage IN and chamber I30 for discharge into the passage 13 through the outlet or orifice I3I. The position of the fitting H3 may be regulated or adjusted by the manipulating member H8 to vary or control the amount of air to be mixed with the fuel for idling purposes. A fuel and air mixture from the passage I26 is also admitted to the mixture outlet passage I3 through the supplemental orifice i29 which comes into operation immediately upon slight movement of the thrott-le valve 16 away from closed position. Thus the supplemental orifice I29 together with the idling orifice I28 supplies fuel and air mixture for the engine during increasing speed of the engine and before the high speed jet 93 comes into operation viz. before it begins to discharge fuel into the venturi it. The amount of fuel admitted to the Well 9'! may be regulated by adjusting the realtive position of the fitting an to change the position of the needle valve I8 3 in the fuel orifice 98. Such rotation of the fitting I92 does not interfere with the mixing of air and fuel in the chamber IE3! as the fuel orifice I08 is always in communication with the chamber IIlI irrespective of the realative position of adjustment of the needle valve id and fitting I02 under all operating conditions. The speed of the engine is controlled by the position of the valve disk 16 the latter serving to control the fuel and air mixture passing through the mixture outlet 13 into the engine.

It should be noted that with my invention an exceedingly compact arrangement of elements is attained wherein the fioat mechanism is arranged directly below the mixing passage so that the distance that the fuel must be lifted from the fuel level L in the bowl I4 to the discharge orifice or jet 93 is reduced to a minimum. Another feature that makes this possible is the arrangement of the axis of the venturi and mixture outlet passage being out of alignment with the axis of the air inlet 52 so that while high efiiciency of the venturi is assured, the distance through which the fuel must be elevated for discharge from the main jet 8% is correspondingly reduced whereby the carburetor operates at a very high degree of efficiency. Furthermore another feature of compactness resides in a fuel Well being disposed in a depending portion of the carburetor body projecting through the central space formed by the doughnut or annularly shaped fioat member 39. Furthermore the adjustment of the needle Hill and of the air regulating valve IIQ are readily accessible at the upper part of the carburetor so that there is no interference of the adjustable elements of the construction with any other mechanism placed close to the carburetor. The offset arrangement of axes DD and EE of fittings IE2 and 96 provides for an angular position of the tubular needle valve member me so that the major amount of fuel discharged from the orifice or main jet 93 occurs at the right hand side of member I03 as shown in Figures 2. This substantially eliminates any tendency for air stream entering air inlet 52 from exerting a downwardly acting pressure on the fuel moving upwardly in tube 92 for discharge from the orifice 93. The fuel chamber I4 is vented to 8. the atmosphere for purpose of presure equaliza tion by means of a duct 99. Due to the compact arrangement of my invention an effective reduction in weight of the parts and a corresponding saving of metal is effected.

It is apparent that, within the scope of the invention, modifications and different arrangements may be made other than is herein disclosed, and the present disclosure is illustrative merely, the invention comprehending all variations thereof.

What I claim is:

1. In a carburetor, in combination, a body; a fuel receptacle disposed directly beneath the body; a float controlled valve for establishing a predetermined fuel level in said receptacle; a fuel Well associated with said body; a mixing passage including a venturi formed in said body; an air inlet passage formed in the body in communication with said mixing passage; the axes of said mixing and air inlet passages being in parallel relationship with the axis of said mixing passage being nearer to the fuel level in said receptacle than the axis of said air inlet passage; a fuel discharge orifice arranged to discharge fuel from said well into the mixing passage; a member extending through said orifice for regulating the flow of fuel from said receptacle to said fuel well; the longitudinal axis of said member being out of alignment with the axis of said fuel discharge orifice.

2. In a carburetor, in combination, a body; a fuel receptacle disposed directly beneath he body; a float controlled valve in said receptacle for establishing a predetermined fuel level in said receptacle; a fuel well associated with said body; a mixing passage including a venturi formed in said body; an air inlet passage formed in the body in communication with said mixing passage; the axes of said mixing and air inlet passages being in parallel relationship with the axis of said mixing passage being nearer to the fuel level in said receptacle than the axis of said air inlet passage; a fuel discharge orifice arranged to discharge fuel from said well into the mixing passage; a member extending through said orifice for regulating the flow of fuel from said receptacle to said fuel well; the longitudinal axis of said member being out of alignment with the axis of said fuel discharge orifice.

3. In a carburetor, in combination, a body; a fuel receptacle associated with said body; a valve; float means associated with said valve for controlling the fuel level in said receptacle; a fuel well formed in said body; a mixing passage including a venturi formed in said body; an air inlet passage formed in the body in communication with said mixing passage; the axis of said mixing passage being nearer to the fuel level in said receptacle than the axis of said air inlet passage; a fuel discharge orifice arranged to discharge fuel from said well into the mixing passage; a member extending through said orifice for regulating the flow of fuel from said receptable to said fuel well; the longitudinal axis of said member being angularly disposed with respect to the axis of the fuel discharge orifice; a second orifice arranged in the wall of the mixing passage for discharging an idling mixture into said mixing passage; said member having a passage therethrough for conveying fuel from said well to said second mentioned orifice.

4. In a carburetor, in combination, a body; a fuel receptacle disposed beneath the body; a

valve; floatmean's associated with: said valve through said main orificefo'r regulating the flow' of' fuel from said receptacle to said fuel well; said member being laterally offset with respect to? the center of the mainfuel discharge orifice; raj-second orifice arranged in the wall of the mixing passage for discharging an idling mixture into said mixing passage; said member having a passage therethro'ugh for conveying fuel from said well-to said second mentionedi orifice; a supplemental' air inlet in communication with said second mentioned orifice for admitting air to the fi-iel prior to its discharge from saidsecond mentioned orifice, and valve means in said supplemental air inlet for regulating the amount of air to be mixed with the fuel discharged from said second mentioned orifice.

5; In a carburetor, in combination, a body: a fuel receptacle di'sposed directly beneath the body adaptedto be connected to a fuel supply" tube: a value; a" float in said receptacle associated with said valve for controlli'ngthe flow of fuel to said receptacle; said body having a portion: extending through said receptacle"; a fuel well formed in saidportion a mixing passage including a venturi formed in said body; an air inlet passage formed inthe body and in: communication with said mixing passage; theaxisofsa-id mixing passage being nearer to the fuel level insaid receptacle than the axis of said air inlet passage; a fuel discharge orifice arranged to discharge fuel from said well into the mixing passage; a manually-adjustable member extending through said orifice for" regulating the flow of that fromsaid receptacleto said fuel well;- the" longitudinal axis of said member being angularly disposed with respect to the axis of the fuel discharge orifice; a/ second orifice arranged in the wall of the mixing passage for discharging an idling mixture into said mixing" passage; said manuallyadjustable" member having a passage therethrough for conveying fuel from said well tosaid second menfiioned orifice; a supplemental air inlet in connmunication with. said second mentioned orifice for admitting air to the fuel prior to its dischargefromsaid: secondl mentioned. orifice; and value means associated with. said. supplemental air inlet; for regulating. amount; of air to be mixed the fuel discharged: from said. second mentioned orifice;

fit. In a. carburetor,. in; coinbination,- a: body; a

float chamber positioned directly beneath the body; an annular-1p shaped float disposed in said float chamber; valve means associated with said float for controlling the flow of fuel into said float chamber from a fuel supply; a fuel well associated withsaid body; said body being formed with a mixing passage including a venturi; an

air: inlet. passage formed said body and in communication with saidl-venturi; the axis of said venturi. being parallel to and out ofalignn'icntwith the axis of said air inlet; a main fuel discharge. orifice for discharging fuel from: said We'll into the restricted portion of said; venturi; an elongated member extending through said mainfuel discharge orifice into said fuel well and having a valveportion for controlling the amount of f uei flowing into saidwell fiD 'I' the final chamher: thelongitudinal axis of said member being angular-Iv disposed with respect tothe axisof themai-m fuel discharge orifice; an idling orifice formed in the wall of" said mixture outlet;- said elongated member having a passage therein for conveying fuel to said idling orifice; and means including a: supplemental air inlet for supplying air to the fuel priorto its discharge through the idling orifice;

7; In a carburetor, in combination; a body; a float chamber associated with the body; anannularly shaped float pivotally supported i'rr said float chamber? valve means crmnect'cd with said floatfor controlling the flow of fuel from a fuel supply intcv said float chamber;- a fuel well associated with said body; said body being formed with a; mixing pass-age. comprising a cylindrical chamber and aventuri; an air inletpassage" of cylindrical? shape of 'great'erareain cross section than the cylindrical chamber formed in said: body in communication with said venturi; the axis of said venturi and cylindrical chamber-being'nearer tothe fuel level in said float chamber than the axis of said" air inlet; a main fuel discharge orifice for discharging fuel from said well into said mixing passage; a manually adjustable member extending through the main f-uel discharge orifice into said fuel well and having a valveporticn: for controlling the amount of fuel flowing into said well from the float chamber an idling orifice formed the wall of" saidmixing passage; said member having a passage therein for conveying fuel to said idling orifice: means including asupplemental air inlet for supplying air to the fuel prior to its discharge through the from the. main orifice.

8. In a carburetor, in combination, abodiv; a

float chamber positioned directh beneath the body: an annularly shaped float pivotally supported said float chamber; valve means connected with said float for controlling the flow of fuel froma fuel supply into said float chamber; said body having a depending portion extending into the central space formed by said annular float; a fuel well formed in said depending portion; said body being formed with amixing passage including a cylindrical chamber: an' air inlet passage of greater cross-sectional area: than the cylindrical chamber formed said body communicationwith said mixing passage the axisof said mixing passage being nearer tothe fuel level in said float chamber than the axis of said air inlet passage; a main fuel discharge orifice for' discharging fuel from said well into the mixing passage; an elongated member extending through the main fuel discharge oriflce into said fuel welland having a valve portion for controlling the amount of fuel flowing into said well from the float chamber;

the Wall ot'sa-id mixture outlet: said elongated member having a passage thereinfor conveying fuel to said idling orifice; means including a supplemen'tali air inlet" for supplying air to the fuel prior to its-'- discharge through the idling orifice;

meansfor regulating the amount of" air supplied to the fuel discharged fromsaid idling orifice"; air bleed passage having communication with said fuel well for admitting air to the fuel in said well prior to its discharge from the main discharge orifice into the mixing passage; a throttle valve in said mixing passage; a supplemental orifice in the wall of said mixing passage spaced from said idling orifice; said idling and supplemental orifices being arranged on opposite sides of the throttle valve when the latter is in closed position; said supplemental orifice being supplied with fuel and air from the passage in said elongated member and said supplemental air inlet.

9. In a carburetor, in combination, a carburetor body having a depending portion; a fuel receptacle positioned directly beneath the body; an annular float member surrounding said depending portion and disposed in said receptacle; valve means actuated by said float for controlling the fiow of fuel from a fuel supply into said receptacle; a fitting disposed in a bore in the depending portion of the body; a mixing passage including a venturi formed in said body; an air inlet formed in the body in communication with the venturi; the axis of said venturi being spaced from the axis of said air inlet; a fuel Well associated with said fitting; a second fitting threaded into an opening in the body and disposed above the venturi; the axis of said second fitting being parallel to but out of alignment with the axis of said first mentioned fitting; a fuel discharge orifice in communication with said fuel well for discharging fuel into said venturi; an elongated valve member carried by the fitting disposed above the venturi and extending into the fuel well; means for adjusting the upper fitting to regulate the position of said elongated member for controlling the flow of fuel from said receptacle into said fuel well; the longitudinal axis of said elongated member being angularly disposed with respect to the axis of said fuel well.

10. In a carburetor, in combination, a carburetor body having a depending portion; a fuel receptacle positioned beneath the body; an annular float member surrounding said depending portion and disposed in said receptacle; valve means actuated by the position of said float for controlling the fiow of fuel from a fuel supply into said receptacle; a mixing passage including a venturi formed in said body; an air inlet formed in the body in communication with the venturi; the axis of said venturi being spaced from the axis of said air inlet; a fuel well formed in the depending portion of said body; a fitting threaded into an opening in the body and disposed above the venturi; the axis of said fitting being parallel to but out of alignment with the axis of said fuel well; a fuel discharge orifice in communication with said fuel well for discharging fuel into said mixing passage; an elongated valve member carried by the fitting extending into the fuel well; means for adjusting the fitting to regulate the position of said elongated member for controlling the fiow of fuel from said receptacle into said fuel well; the longitudinal axis of said elongated member being angularly disposed with respect to the axis of said fuel well; said elongated member being arranged at one side of the axis of the fuel discharge orifice whereby fuel is discharged by said orifice at one side of said elongated member.

11. In a carburetor, in combination, a body; a fuel receptacle disposed beneath the body; a float controlled valve in said receptacle for establishing a predetermined fuel level in said receptacle; a fuel well formed in said body; a mixing passage comprising a cylindrical chamber and a venturi, the axis of the venturi being coincident with the axis of the cylindrical chamher; a cylindrically shaped air inlet passage of greater cross-sectional area than said cylindrical chamber and having its axis eccentrically arranged with respect to the venturi and cylindrical chamber; the axis of the cylindrical chamber and venturi being nearer to the fuel level in said receptacle than the axis of said air inlet passage; a fuel discharge orifice arranged to discharge fuel from said well into the mixing passage; and a member extending through said fuel discharge orifice for regulating the fiow of fuel from said receptacle to said fuel Well.

12. In a carburetor, in combination, a body; a fuel receptacle disposed beneath the body; a float controlled valve in said receptacle for establishing a predetermined fuel level in said receptacle; a fuel well formed in said body; a mixing passage comprising a cylindrical chamber and a venturi, the axis of the venturi being substantially coincident with the axis of the cylindrical chamber; a cylindrically shaped air inlet passage of greater cross-sectional area than said cylindrical chamber and having its axis eccentrically arranged with respect to the axis of the venturi and cylindrical chamber; the axis of the cylindrical chamber and ventui being nearer to the fuel level in said receptacle than the axis of said air inlet passage; a tube in communication with said fuel Well and terminating in said venturi, the end of the tube in the venturi being open to form a discharge orifice arranged to deliver fuel from said well into the venturi, and means for metering the flow of fuel from the receptacle to the fuel well.

13. In a carburetor, in combination, a body; a fuel receptacle disposed beneath the body; a float controlled valve in said receptacle for establishing a predetermined fuel level in said receptacle; a fuel well formed in said body; a mixing passage comprising a cylindrical chamber and a venturi, the axis of the venturi being substantially coincident with the axis of the cylindrical chamber; a cylindrically shaped air inlet passage of greater cross-sectional area than said cylindrical chamber and having its axis eccentrically arranged With respect to the axis of the venturi and cylindrical chamber; the axis of the cylindrical chamber and venturi being nearer to the fuel level in said receptacle than the axis of said air inlet passage; a tube in communication with said fuel well and terminating in said venturi, the end of the tube in the venturi being open to form a discharge orifice arranged to deliver fuel from said well into the venturi, and adjustable valve means for regulating the admission of fuel into the fuel well from the receptacle,

EDWARD H. FOSTER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,453,490 Bessom .May 1, 1923 1,523,095 Zarracina Jan. 13, 1925 1,741,401 Bryan Dec. 31, 1929 1,758,954 Linn May 20, 1930 1,823,017 Wolfard Sept. 15, 1931 1,840,279 Sturm Jan. 5, 1932 1,849,720 Parkin Mar. 15, 1932 2,270,369 Danielsen Jan. 20, 1942 2,419,956 Kuzelka May 6, 1947 

